| Computer Code: |
TUFA |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Quaternary Period (Q)
— Quaternary Period (Q) |
| Lithological Description: |
Tufa is a sedimentary rock composed of calcium carbonate or silica, formed by evaporation as a thin, surficial, soft, spongy, semifriable encrustation around the mouth of springs, seeps or along streams carrying calcium carbonate in solution, and exceptionally as a thick deposit along lake shores. Travertine is a hard, dense variety of tufa; it also occurs in caves as stalactites and stalagmites. Synonyms: sinter, travertine. |
| Definition of Lower Boundary: |
none recorded or not applicable
|
| Definition of Upper Boundary: |
none recorded or not applicable
|
| Thickness: |
none recorded or not applicable
|
| Geographical Limits: |
none recorded or not applicable
|
| Parent Unit: |
Chemical deposits (CHEMD)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| none recorded or not applicable |
| Reference(s): |
| McMillan, A A, and Powell, J H. 1999. The classification of artificial (man made) ground and natural superficial deposits. British Geological Survey Research Report, RR/99/04. |
| Hallsworth, C R, and Knox, R W O'B. 1999. BGS Rock Classification Scheme Volume 3. Classification of sediments and sedimentary rocks. British Geological Survey Research Report, RR 99-03. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E237
E014
E203
E219
E217
|
